Flashcards in EQ3 Deck (39)
what eustatic factors affect longer term sea level changes?
what isostatic factors affect longer term sea level changes?
post glacial adjustment
what do you find on an emergent coastline?
raised beaches with fossil cliffs
what do you find on a submergent coastline?
what local factors increase flood risk on some low lying and estuarine coasts?
degree of subsidence
how does climate change directly increase coastal flood risk?
frequency of storms
magnitude of storms
what is the maldievs' average level above sea level?
what is the maldives' hgihes point?
what are the 2 reasons for sea level rise?
ice caps and glaciers melting
what's happening in kiribati?
president anote bought 20km2 of fijian land, so they have refuge somewhere else.
it will be used immediately for agriculture and fish farming projects, to guarantee the nation's food security.
what are rising sea levels causing in kiribati?
contaminating its ground water sources and affecting its ability to grow crops.
what kind of landscape is kiribati?
33 widely spaced islands in the Pacific Ocean
very low lying sand and mangrove atolls.
what is an atoll?
a ring-shaped reef, island, or chain of islands formed of coral.
what policy has the government launched in kiribati?
"migration with dignity" policy to allow people to apply for jobs in neighbouring countries like new zealand.
what is eusostatic change?
when sea level rises or falls-global.
what is isostatic change?
when land level rises, relative to the sea-local
what isostatic changes happen during glacial periods?
weight of ice sheets makes ground sink-isostatic subsidence.
what isostatic changes happen during interglacial periods?
reduced weight of the ice causes land to rise-isostatic recovery/uplift.
how does tectonic activity cause isostatic change?
-uplift of mountain ranges +coastal land at destructive+collision plate boundaries
-local tilting of land, eg local Mediterranean ports submerged and others stranded at sea level-turning of strata.
what is an example of a tsunami causing eusostatic change?
at banda aceh in indonesia, after the 9.1 magnitude earthquake in 2004, some places were permanently submerged.
what are 2 human factors affecting coastal retreat?
what are the effects of coastal flooding in australia?
-$226billion worth of infrastructure and homes at risk if sea levels rise by 1.1m.
-groundwater supplies may be affected by salt intrusion.
-Great Barrier Reef, mangrove forests, salt marshes, sea grass will be trapped between rising sea levels and coastal defences.
-coral reefs more than 50m deep will die
-salt water will be pushed up estuaries due to sea level rise, affecting freshwater habitats like in kakadu national park.
what are the effects of coastal flooding on the philippines?
-$5.8billion a year
-sea level rise higher than global average-5.8mm a year- because of trade winds and currents move water to islands.
-Manila Bay-mangroves, corals, and sea grass destroyed by pollution and overexploitation, reducing their ability to protect the backshore from sea level rise.
-fishermen-loss to community
in bangladesh, what area of flooding would happen if sea levels rose by 1.5m?
how many people in bangladesh have their drinking water contaminated by salt?
what unesco world heritage site may be lost to sea level rise and why is this relevant?
Sundarbans- largest mangrove forest in the world, located in the Bay of Bengal.
would reduce protection from coastal floods.
why are high tide levels rising in bangladesh?
land subsidising due to drainage, dredging of the channel, natural compaction of the delta.
what is accretion?
the process of coastal sediment returning to the visible portion of a beach or foreshore following a submersion event
how does a raised beach form and an example?
land rising because of isostatic uplift so former shoreline platforms and their beaches were raised above present sea level.
eg isle of arran-3 distinct raised beaches